The present disclosure provides a method and a device for wireless communications. A first node receives a first signaling and a second signaling; and transmits a first radio signal in a first slot; herein, the first signaling is used for indicating a first time window, an index for the first slot in the first time window is a first index, the second signaling is used for determining a first time offset; when the first radio signal is transmitted in a mainlink, the first index is used for generating the first radio signal; when the first radio signal is transmitted in a sidelink, the second index is used for generating the first radio signal, the second index is related to both the first time offset and the first index. By adjusting and optimizing timing relations between different nodes by different indexes, the present disclosure prevents interferences and increases the efficiency.